Need help with formula H(t) = −16t^2 + vt + s
My question is:
Jesse kicks a soccer ball off the ground and in the air with an initial velocity of 29 feet per second. Using the formula H(t) = −16t^2 + vt + s, what is the maximum height the soccer ball reaches?

But when I graphed the equation, the parabola was at a maximum and it said the highest was 26, so I'm not sure what I've done wrong.

My choices are:
13.1
13.5
13.8
14.2

Question

Need help with formula H(t) = −16t^2 + vt + s
My question is:
Jesse kicks a soccer ball off the ground and in the air with an initial velocity of 29 feet per second. Using the formula H(t) = −16t^2 + vt + s, what is the maximum height the soccer ball reaches?

But when I graphed the equation, the parabola was at a maximum and it said the highest was 26, so I'm not sure what I've done wrong.

My choices are:
13.1
13.5
13.8
14.2

agent0smith · Answer

$$\large H(t) = −16t^2 + vt + s $$ It's kicked off the ground, so s = 0. v=29, so

$$\large H(t) = −16t^2 + 29t $$

agent0smith · Answer

I'm not sure how you got the maximum height as 26... show your work?

compassionate · Answer

You want to use the equation $$-\frac{ b }{ 2a }$$

To get the maximum height. Then plug that into the original equation to get the other point.

Then, you can use the quadratic formula to get the two points were x = 0.

anonymous · Answer

I forgot the second formula! Thank you guys both!